Two-Dimensional Nuclear Magnetic Resonance Spectra of Cellulose and Cellulose Triacetate

Kowsaka, Keisuke; Okajima, Kunihiko; Kamide, Kenji

doi:10.1295/polymj.20.1091

Cited by 27 publications

(17 citation statements)

References 16 publications

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“…Moreover, unit A was substituted at position →4), whereas unit B was substituted at position →3). The results were in good agreement with the chemical shifts of acetylated cellulose (34) and (1→3)-β-D-glucopentaose peracetate (35). Finally, the ROESY spectrum (SI Appendix, Fig.…”

Section: Resultssupporting

confidence: 77%

Novel mixed-linkage β-glucan activated by c-di-GMP in Sinorhizobium meliloti

Pérez-Mendoza

Rodrı́guez-Carvajal

Romero-Jiménez

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

109

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An artificial increase of cyclic diguanylate (c-di-GMP) levels in Sinorhizobium meliloti 8530, a bacterium that does not carry known cellulose synthesis genes, leads to overproduction of a substance that binds the dyes Congo red and calcofluor. Sugar composition and methylation analyses and NMR studies identified this compound as a linear mixed-linkage (1→3)(1→4)-β-D-glucan (ML β-glucan), not previously described in bacteria but resembling ML β-glucans found in plants and lichens. This unique polymer is hydrolyzed by the specific endoglucanase lichenase, but, unlike lichenan and barley glucan, it generates a disaccharidic →4)-β-DGlcp-(1→3)-β-D-Glcp-(1→ repeating unit. A two-gene operon bgsBA required for production of this ML β-glucan is conserved among several genera within the order Rhizobiales, where bgsA encodes a glycosyl transferase with domain resemblance and phylogenetic relationship to curdlan synthases and to bacterial cellulose synthases. ML β-glucan synthesis is subjected to both transcriptional and posttranslational regulation. bgsBA transcription is dependent on the exopolysaccharide/quorum sensing ExpR/SinI regulatory system, and posttranslational regulation seems to involve allosteric activation of the ML β-glucan synthase BgsA by c-di-GMP binding to its C-terminal domain. To our knowledge, this is the first report on a linear mixed-linkage (1→3)(1→4)-β-glucan produced by a bacterium. The S. meliloti ML β-glucan participates in bacterial aggregation and biofilm formation and is required for efficient attachment to the roots of a host plant, resembling the biological role of cellulose in other bacteria.exopolysaccharides | cyclic diguanylate | plant-microbe interactions

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Section: Resultssupporting

confidence: 77%

Novel mixed-linkage β-glucan activated by c-di-GMP in Sinorhizobium meliloti

Pérez-Mendoza

Rodrı́guez-Carvajal

Romero-Jiménez

et al. 2015

Proc. Natl. Acad. Sci. U.S.A.

109

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“…16 The water elimination Fourier-transform (WEFT) method was applied for 1 H NMR measurements to diminish peak intensity originating from HDO. Homonuclear 1 H shift correlation spectroscopy e H COSY) and heteronuclear 13 C-1 H shift correlation spectroscopy (CH-COSY) were recorded as follows:…”

Section: Nmr Measurementsmentioning

confidence: 99%

“…Other operating conditions are indicated in the previous paper. 16 (2) The CH COSY spectrum was recorded using the pulse sequence method described in the previous study. 16 The mixing time L1 was set up to be 2.0ms ( = 1/(4lc-H)), where lc-H is the ayerage coupling constant between C and H nuclei.…”

Section: Nmr Measurementsmentioning

confidence: 99%

“…16 (2) The CH COSY spectrum was recorded using the pulse sequence method described in the previous study. 16 The mixing time L1 was set up to be 2.0ms ( = 1/(4lc-H)), where lc-H is the ayerage coupling constant between C and H nuclei. Operating conditions are follows: 13 Figure 1 illustrates the possible 8 AHG units constituting NaCS chains, predicting the existence of magnetically non-equivalent 48 13 C and 56 1 H nuclei.…”

Section: Nmr Measurementsmentioning

confidence: 99%

“…The 1 H peak at 4.42 ppm (H 2 proton) is correlated with two 13 C peaks at 80.1 and 69.6 ppm and therefore, the peak at 4.42 ppm is excepted to be an overlapping peak of H 2 proton and an other proton. The 13 C peak at 69.6 ppm is assigned to c6 carbon because the c6 carbon peak is without exception observed in the highest magnetic field in the spectra of cellulose, 16 CA/ 6 CN/ 4 and CX. 6 This leads to the conclusion that the 1 H peak at 4.42 ppm originates from H 2 and H 6 (and H 6 ') protons; note that there are two magnetically non-equivalent H 6 protons, H 6 and H 6 '.…”

Section: Nmr Measurementsmentioning

confidence: 99%

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Determination of the Distribution of Substituent Groups in Sodium Cellulose Sulfate: Assignment of 1H and 13C NMR Peaks by Two-Dimensional COSY and CH-COSY Methods

Kowsaka¹,

Okajima²,

Kamide³

1991

Polym J

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ABSTRACT:An attempt was made to give full assignment to the 1 H and 13 C NMR spectra of sodium cellulose sulfate (NaCS) dissolved in D 20 and to determine the molar fractions of all possible 8 kinds of anhydroglucopyranose (AHG) units constituting NaCS molecule. For this purpose five NaCS samples with the total degree of substitution ranging from 0.61 to 2.42 were synthesized by three different methods. Using a NaCS sample 1 H and 13 C peaks for 2,3,6-trisubstituted AHG were reasonably assigned by two-dimensional (2D) homonuclear 1 H correlation spectroscopy (COSY) and heteronuclear 1 H-13 C correlation spectroscopy (CH-COSY) techniques. In the same manner, 1 H and 13 C NMR peaks originating from unsubstituted AHG were assigned by analysis on NaCS with Chemical shifts (o) of protons and carbons in monosubstituted and disubstituted AHG units were calculated using shift factors empirically estimated from the observed o values of trisubstituted and unsubstituted AHG units. The assignments on 1 H NMR peaks for NaCS previously made by Kamide and Okajima [Polym. J., 13, 163 (1981)] on the basis of the peak assignment of cellulose acetate were found to be partly incorrect. The average degree of substitution for each three hydroxyl groups attached to C2, C 3 , and C 6 carbon positions (k=2, 3, and 6) was estimated based on the assignment made here and a relation > > was obtained for the NaCS samples synthesized here.

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Cellulose Esters, Organic Esters

Gedon

Fengi

2000

Kirk-Othmer Encyclopedia of Chemical Technology

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Cellulose is one of nature's most abundant structural materials, providing the primary framework of most plants. For industrial purposes cellulose is derived from two primary sources, cotton linters and wood pulp. Cellulose esters are commonly derived from natural cellulose by reaction with organic acids, anhydrides, or acid chlorides. Cellulose esters of almost any organic acid can be prepared, but because of practical limitations esters of acids containing more than four carbon atoms have not achieved commercial significance. Cellulose acetate is the most important organic ester because of its broad application in fibers and plastics; it is prepared in multi‐ton quantities with degrees of substitution (DS) ranging from that of hydrolyzed, water‐soluble monoacetates to those of fully substituted triacetate. Although cellulose acetate remains the most widely used organic ester of cellulose, its usefulness is restricted by its moisture sensitivity, limited compatibility with other synthetic resins, and relatively higher processing temperature. Cellulose esters of higher aliphatic acids, C 3 and C 4 , circumvent these shortcomings with varying degrees of success. Mixed cellulose esters containing acetate and either the propionate or butyrate moieties are produced commercially in large quantities by Eastman Chemical Co. in the United States. The properties, manufacturing methods, uses, economics, and safety of organic esters of cellulose are discussed.

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Two-Dimensional Nuclear Magnetic Resonance Spectra of Cellulose and Cellulose Triacetate

Cited by 27 publications

References 16 publications

Novel mixed-linkage β-glucan activated by c-di-GMP in Sinorhizobium meliloti

Novel mixed-linkage β-glucan activated by c-di-GMP in Sinorhizobium meliloti

Determination of the Distribution of Substituent Groups in Sodium Cellulose Sulfate: Assignment of 1H and 13C NMR Peaks by Two-Dimensional COSY and CH-COSY Methods

Cellulose Esters, Organic Esters

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